Which energy transformation most likely occurs in a steam iron

If the pka of hcho2 is 3.74 and the ph of an hcho2/nacho2 solution is 3.89, it means that

Andrei [34K]

Hi, the question has some missing part. The complete question should be " If the $pK_{a}$ of $HCHO_{2}$ is 3.74 and the pH of an $HCHO_{2}/NaCHO_{2}$ solution is 3.89, it means that -

(a) $[HCHO_{2}]=[NaCHO_{2}]$

(b) $[HCHO_{2}]> [NaCHO_{2}]$

(c) $[HCHO_{2}]< [NaCHO_{2}]$

Which of the options are true?"

Answer: Option (c) is true.

Explanation:

$HCHO_{2}/NaCHO_{2}$ is an weak acid-conjugate base buffer. Hence, in accordance with Henderson-Hasselbalch equation-

$pH=pK_{a}(HCHO_{2})+log(\frac{[CHO_{2}^{-}]}{[HCHO_{2}]})$

Here, pH = 3.89, $pK_{a}$ of $HCHO_{2}$ = 3.74

So, $3.89=3.74+log(\frac{[CHO_{2}^{-}]}{[HCHO_{2}]})$

or, $\frac{[CHO_{2}^{-}]}{[HCHO_{2}]}$ = 1.41 (>1)

So, $[CHO_{2}^{-}]> [HCHO_{2}]$

or, $[NaCHO_{2}]> [HCHO_{2}]$

Hence, option (c) is correct.

6 0

4 years ago

PLEASE HELP ME! What are some patterns or trends that are present in the table of elements?

Sati [7]

Some patterns and trend that are present in the periodic table would be

1. electronegativity (from left-to-right it increases across the table)

2. ionization (from left-to right it increases and from bottom-to-top it increases)

3. electron affinity (same as ionization energy)

4. atom radius (increases opposite way; from right-to-left it increases and from top-to-bottom it increases)

5. melting point (higher melting points with metals and lower melting point with non-metals)

6. metallic character (same as atom radius)

5 0

3 years ago

I need help w this. Questions 4, 5, 6 specifically but if you can help with others that'd be great

Tju [1.3M]

Answer:

456?

Explanation:

Ok

5 0

3 years ago

A compound that conducts electricity when dissolved in water would most likely be classified as

Dimas [21]

Answer:

Electrolyte

Explanation:

A compound that conducts electricity when dissolved in water would most likely be classified as electrolyte.

The ionic compound in solid form do not conduct the electricity but when dissolve in water they separated into ions and have ability to conduct the electricity because of mobile ions that move freely and allow the charge to flow.

The ionic compounds are called electrolyte and electrolyte solution is formed when they dissolve in water.

For example when sodium chloride is placed into water it split into ions and conduct electricity because of mobile ions.

Chemical equation:

NaCl → Na⁺ + Cl⁻

6 0

3 years ago

A particular atom contains 29 electrons, 34 neutrons, and 29 protons. what is the identity of this element and what is its atomi

IgorLugansk [536]

Answer:

Identity = Copper

Atomic Number = 29

Explanation:

Given Data:

Number of Electrons = 29

Number of Neutrons = 34

Number of Protons = 29

Identity and atomic number of Element:

This element can be identified by using two sources, i) Atomic Number ii) Electronic Configuration.

Atomic Number is defined as the number of protons present in the nucleus of an element. As the given number of protons are 29, therefore, the atomic number of this element is also 29.

Secondly, if the element is in neutral state then its number of protons must be equal to the number of electrons present in it. So, in neutral state this element will contain 29 electrons. Therefore, the electronic configuration is as follow,

1s², 2s², 2p⁶, 3s², 3p⁶, 4s², 3d⁹

Now using electronic configuration one can easily identify the position of this element in periodic table. As the valence shell is 4, so it belongs to period 4 and there are 9 electrons in d-subshell so it belongs to transition elemnts and transition element with 9 electrons in d shell is Copper. Also, the stable electronic configuration of copper is written as,

1s², 2s², 2p⁶, 3s², 3p⁶, 4s¹, 3d¹⁰

5 0

3 years ago